Prosthetic liner with proximal seal

ABSTRACT

A prosthesis suspension assembly comprising: a prosthetic socket having an open proximal end and a closed distal end and an interior surface complementally configured to a residual limb of an amputee, an interface or liner for receiving the residual limb and fittingly received in the socket, a distal outer surface of the liner comprises a porous or continuously cavitated, compressible material such as fabric and a proximal outer surface comprising an elastomeric material, a suspension sleeve which seals against the proximal outer surface of the liner and a proximal outer surface of the socket, and a locking pin connected to a distal end of the liner and lockingly retained in a hole in the distal end of the socket and including an air passage therethrough with a one-way valve therein for permitting the exit of air from an interstitial volume occupied buy said compressible material to atmosphere upon ambulation.

PRIORITY

This application is a Continuation-in-Part Application of U.S.application Ser. No. 12/381,146 filed on Mar. 6, 2009, which claimspriority to U.S. provisional application Ser. No. 61/034,323, filed onMar. 6, 2008.

BACKGROUND OF THE INVENTION

During the 1980's, a means of suspending a prosthesis was developedwhich consisted of a docking means fabricated into an interface which,in turn, was rolled onto the distal portion of the wearer's residuallimb. The docking means engaged into the prosthesis, and the prosthesiswas thereby locked in position of attachment to the patient's limb.

Such a means of attachment became standard in the industry. However, ithad drawbacks which ultimately led to its supplantation by othermethods. One major drawback was the tendency of the residual limb topiston, or slip upwards and downwards in the interface upon ambulation.Over the years, it has been thought that pistoning occurred because onlythe distal portion of the limb was involved in the support of theprosthesis. The limited support resulted in a high degree of angular andtorsional stress at the interface of the socket/liner and the residuallimb. The pistoning, in combination with the sucking effect caused bythe interface, caused the limb to change in volume with ambulation. As aresult, the fit of the prosthesis changed with wear throughout the day.It was necessary for the wearer to make use of a thick prosthetic sockon the residual limb in an attempt to compensate for the limb's changein volume during use of the prosthesis and alleviate some of thediscomfort which was experienced as a result of pistoning. However, thesock added an inconvenient bulk to the already awkward task of wearing aprosthesis, as well as creating sanitary issues due to the collection ofsweat and dirt.

In the 1990's, suspension sleeves were used to create a seal between theresidual limb and the prosthesis. As illustrated in FIGS. 1 and 2, thistype of suspension sleeve (4) is an elastic or elastomeric tube which,when properly positioned, forms a seal which encompasses 1) the proximallip of the prosthesis socket (3), 2) the entire portion of theinterfacing layer/liner (5) external to the socket, and 3) a portion ofthe wearer's thigh just above the proximal end (2′) of the interfacinglayer/liner. The sleeve, employed in its sealing capacity, isillustrated in FIG. 2. The seal created by the elastomeric sleeve isable to support a modest vacuum. The vacuum is typically in the range offrom greater than about 2 inches Hg to about 14 inches Hg. One-wayvalves embedded in the prosthesis socket or interfacing layer/liner orpumps are often used to establish and maintain the vacuum.

The sealed socket limb junction of these prior art prostheses largelyeliminates the pistoning problem. Furthermore, such prior art prosthesesincluded a layer of fabric or other porous or continuously cavitatedcompressible material such as, for example, a synthetic foam, whichoverlies the entire interface and occupies an area between the socketand the interface, and serves to “wick” the vacuum to the entire volumeoccupied thereby, yet it prevents the interface from coming into contactwith the socket, effectively establishing a volume over which a vacuumcan be sustained.

However, this method introduces new problems. The upper reaches of theseal extend onto the thigh of the wearer, essentially including the skinof the wearer in the partially evacuated volume. The skin directly underthe sleeve chafes from the elastic motion of the sleeve as the residuallimb compresses and decompresses with the ambulation cycle. Furthermore,bending at the knee causes the sleeve to bunch directly behind the kneeand on the back of the leg above the knee, and stretch tightly in theanalogous positions on the front of the residual limb. Such motion cancause blistering and subsequent infection and pain, even to the extentof requiring the wearer to forego the use of the prosthetic for periodsof time. Nevertheless, the sealing of the partially evacuated volume byextending the sleeve to the wearer's thigh, and the inclusion of thewearer's skin as a bounding surface to the partially evacuated volumehave persisted as part of the solution to the pistoning problems arisingfrom earlier designs.

To overcome such problems, it has been found that when 1) the outersurface of only a distal portion of the interfacing layer/liner iscovered with a porous or continuously cavitated compressible material,2) the proximal portion of the interfacing layer/liner has a sealable,preferably elastomeric outer surface, and 3) the proximal portion of thesleeve extends to and seals against the proximal portion of theinterfacing layer/liner; the pistoning is still greatly reduced, eventhough the seal does not extend up onto the thigh. One such prior artsystem is disclosed in U.S. Pat. No. 7,427,297 to Patterson et al. whichis incorporated herein by reference. Although the Patterson et al.prosthesis includes sealing sleeve 46, the present invention is animprovement in the sealing structure on these types of prostheses.

SUMMARY OF THE INVENTION

A prosthetic liner system surmounting the foregoing problems associatedwith the thigh-sealing liner system, yet maintaining the effectivenessagainst pistoning demonstrated by the thigh-sealing liner system wouldrepresent an advance in the prosthetic liner industry.

In one embodiment, the present invention comprises a prosthetic linercomprised of an elastomeric layer having a distal closed end and aproximal open end. The liner has a proximal edge, an inner surface andan outer surface. The outer surface is comprised of a layer ofcompressible porous or continuously cavitated material (“material”layer) which may be fabric. The liner is adapted to fittingly receive aresidual limb of an amputee wherein the inner surface of the elastomericlayer contacts the residual limb. The material layer overlays the outersurface of the elastomeric layer except for a continuous region of theouter surface extending adjacent the proximal open end. At the materialleading edge, the outer surface transitions from fabric to acircumferentially continuous region of the elastomeric layer comprisinga circumferentially continuous sealable surface.

In a preferred embodiment, the prosthetic assembly of the presentinvention comprises a monolithic prosthetic socket having an innersurface and an outer surface, a closed distal end, an open proximal end,a proximal edge and a proximal outer surface region surrounding saidproximal end and wherein said inner surface is configured to besubstantially complimentary to the shape of a residual limb of anamputee. The assembly includes a prosthetic liner having an innersurface and an outer surface, a closed distal end and an open proximalend and wherein the inner surface is adapted to conform to the shape ofa residual limb which is fittingly retained therein when donned. Theliner further includes a proximal outer surface region surrounding theproximal end extending from a proximal edge of the liner to anintermediate edge and a distal outer surface region extending from saidintermediate edge to the distal end of the liner. The distal outersurface region of the liner being covered with a porous or continuouslycavitated compressible material such as fabric, but not limited thereto.The proximal outer surface region and the compressible material defininga substantially continuous surface for the liner such that when theliner is mounted within the socket, the distal outer surface regioncovered with the compressible material is fittingly received in thesocket to thereby define and sustain an interstitial area between theinner surface of said socket and the outer surface of the liner occupiedby the compressible material. The liner, when mounted in said socket,having the intermediate edge disposed adjacent to and within theproximal edge of said socket, and the proximal outer surface region ofthe liner extending away from said proximal edge of the socket. Theprosthetic assembly also includes a sealing open-ended sleeve having afirst end and an opposite second end. The sealing sleeve being mountedin sealing engagement over the proximal outer surface region of saidsocket and the proximal outer surface region of said liner with thefirst end overlapping the proximal outer surface region of said socketand said second end overlapping and terminating within the proximalouter surface region of said liner. As the amputee ambulates, airtrapped within the interstitial area occupied by the compressiblematerial is forced to evacuate therefrom through the compressiblematerial and through the interface between the sealing sleeve, theproximal outer surface region of said socket and the proximal outersurface region of said liner.

In the preferred embodiment of the prosthetic assembly of the presentinvention as described above, the liner, compressible material andsealing sleeve are comprised of materials selected such that a vacuumfrom above about 0 inches Hg to about 15 inches Hg is capable of beingmaintained in the interstitial area occupied by the compressiblematerial upon ambulatory motion.

In another preferred embodiment, the prosthetic assembly of the presentinvention comprises a pin mounted to the distal end of the liner whichengages a hole or cavity in the prosthesis socket. The pin comprises anouter configuration that engages with a locking mechanism for lockingthe prosthesis onto the residual limb. The pin further comprises aninternal passageway with a one-way valve mounted therein. The internalpassageway upstream of the one-way is in fluidic communication with theinterstitial region occupied by the compressible material. The internalpassageway downstream of the one-way valve is in fluidic communicationwith the surrounding atmosphere. Alternatively, the pin could beconnected to a vacuum pumping system mounted externally of theprosthesis such as around a pylon of an artificial leg adapted to beconnected to the distal end of the socket or could be fluidicallyconnected to a pumping system mounted internally of the prosthesis suchas within a cavity inside of a pylon. With any of the abovearrangements, air within the volume of the interstitial region will beforce to exit through the one-way valve either by amputee ambulationand/or suction created by the pumping system.

The present invention is effective over a range of liner lengths. Byliner length, it is meant the distance from the distal tip of the linerto the proximal edge of the proximal open end. Liner lengths in therange of from about 8 inches to about 30 inches are preferred, withlengths in the range of from about 12 to 24 inches more preferred. Ingeneral, it is desirable that the liner have a length such that, whenworn, it extends at least about 5 inches up onto the wearer's residuallimb as measured from the residual limb's most distal point.

The present invention makes use of the fitting parameters which arestandard in the art, and thus, a liner which would be correctly fittedfor the current thigh-seal method is generally correctly fitted for thepurposes of the present invention. However, liners which may beconsidered uncomfortably tight or snug for use with the currentthigh-seal method can, in some cases, be used comfortably with thesuspension system of the present invention.

The liner of the present invention comprises an inner surface and anouter surface. The inner surface faces the residual limb, and in theabsence of other lining materials, contacts or interfaces with thesurface of the residual limb. The inner surface is conveniently a layerof elastomeric material preferably of a type compatible with longperiods of dynamic wearer contact. Such materials are known in the artand may include the following polymers, as well as gels which comprisethem: polyurethanes; block copolymers such as styrene block copolymers,general non-limiting examples of which may include SEBS-, SEPS-, SEEPS-,SEEBS-, and other type styrene block copolymers. Further non-limitingexamples of styrene block copolymers which may be useful in the liner ofthe present invention include so called “controlled distributionpolymers,” such as, for example, those disclosed in U.S. Pat. No.7,226,484; United States Patent Application Publication No. 20070238835;and United States Patent Application Publication No. 20050008669. Otherpotentially useful polymers may include certain so-called “crystalline”polymers, such as, for example, polymers disclosed in U.S. Pat. Nos.5,952,396; 6,420,475; 6,148,830 and 6,148,830. The above list isnon-limiting, and in general, the list of acceptable polymers and gelsincludes those known in the art to be useful for the fabrication ofprosthetic liners. By the term “gel,” is meant a polymer which has,associated with it, through means known in the art such as absorption,mixing, or other, a plasticizer. Gels which do not have a tendency todelaminate from the material layer are preferred.

It should be noted that the benefits of the present invention may beobtained even if the material layer contains other components, such asother layers of flexible materials (even if not elastomeric) as long asthe surface of the material layer against which the suspension sleeveseals, described infra, is capable of sustaining the required vacuum.

Another aspect of the present invention is that the distal portion ofthe liner is modified to have or is covered with a porous orcontinuously cavitated compressible material. The compressible materialdoes not extend to the proximal edge of the liner meaning that allpoints of the leading edge of the porous or continuously cavitatedcompressible layer are at least 1 centimeter away from all points on theproximal edge of the liner, and in other embodiments, at least 3, 5, 8and 12 centimeters from all points on the proximal edge of the liner. Inadditional embodiments, the leading edge of the porous or continuouslycavitated compressible layer and the proximal edge of the liner each liein spaced-apart non-parallel planes and still, in other embodiments, theplanes are parallel to each other and perpendicular to the long axis ofthe liner.

In one embodiment, the compressible material comprises fabric thatoverlies a distal portion of the interface or elastomeric layer. Inanother embodiment, the compressible material is in the shape of a linerwhich slips over the distal end of the liner. In another embodiment, thecompressible material is bonded to the elastomeric layer. Includedwithin, but not limiting the meaning of “bonded” is fabric that isglued, molded, dipped, affixed, adhered, or otherwise immobilized uponthe surface of the elastomeric layer. In yet another embodiment, thecompressible material can be integral to the elastomeric layer. This canbe accomplished when the connection between the layers is a result ofmelting or other processes such as chemical processes, or theelastomeric layer is superficially processed to create a compressiblelayer from the elastomeric layer itself, such as, for non-limitingexample, chemically or thermally treating the upper surface of theelastomeric layer to cause the upper surface to form a foam.

The liner can be of a wide range of thicknesses. In preferredembodiments, the liner has a thickness in the range of from about 1millimeter to 6 millimeters, or even thicker or thinner, with a morepreferred thickness in the range of from about 2 to about 4 millimeters.In general, it is not necessary for the thickness of the liner to beuniform throughout in order to obtain the benefits of the presentinvention. The present invention can be used on liners having thicknessprofiles which are non-uniform or extraordinarily thick or thin, such asprofiles reflecting a material layer having a strategic distribution ofextra cushioning or support, such as may be required for therapeuticpurposes. Furthermore, the interface layer can comprise additionallayers of uniform or non-uniform thickness, such as may be utilized tosupport or cushion certain regions of the liner. In general, the term“liner” also includes elastomeric layers which, optionally, comprisesmultiple layers of elastomeric materials adhered together.

It is, however, strongly preferred that the face of the proximal portionof the interface intended to contact the inner surface of the intendedsuspension sleeve be of such a quality that a seal is formed between theliner and the suspension sleeve which can sustain a moderate vacuum inthe range of from about 2 inches Hg to about 14 inches Hg for longenough to enable the wearer to experience the benefits of the inventionfor significant periods of time, such as, for example at least about 0.5hrs, and more preferably, at least about 1, 2 or 3 hours.

In yet another embodiment the seal, when formed from an assemblycomprising the liner, the prosthetic socket and the sleeve, as well asthe distally connected pin having a one-way valve therein permitting theexit of gas trapped in the interstitial region occupied by thecompressible material, can sustain a vacuum in the foregoing range forat least 10 or 20 minutes, and preferably for at least 30, 40, 50 or 60minutes of ambulatory motion. It should be noted that because one-wayvalves may vary in efficiency, the ability of the assembly to meet theforegoing time standards is a property not of the seal itself, but ofthe seal/valve combination.

As noted above, the liner also comprises a porous or continuouslycavitated compressible material or “material.” By “porous” is meant amaterial comprising interconnected cavities which vent to the surface ofthe material through channels or other cavities. Fabrics, particularlythose of sufficient heaviness, as well other types of usable materials,such as foams and sponges are generally porous. By “continuouslycavitated” is meant a material whose volume comprises interconnectedcavities which are continuous with the exterior of the material.Lattice-type structures (i.e., those having interconnected cavities ofregular shape and size) qualify as “continuously cavitated.”

The material creates a volume over which a vacuum can be maintained. Itscompressibility, even if only slight or incompletely reversible, such asin the case of most fabrics, enables the material, upon seeking toexpand its volume after compression, to aid in the creation of a vacuumin the space bounded by the liner, the suspension sleeve, and theprosthetic socket (the “interstitial volume”). Furthermore, uponambulation, the compressibility of the material enables a largerproportion of the air in the interstitial volume to be evacuated, eitherthrough the one-way valve, as discussed infra, or through the interfacesbetween the sleeve and the prosthesis or the sleeve and the proximalportion of the liner. Preferably, the material is a layer of fabric withsufficient heaviness and compressibility that it can define a volumeover which a moderate vacuum in the range of from about 2 inches Hg toabout 14 inches Hg can be established upon ambulatory motion.

As indicated infra, the material is distributed over the distal portionof the interface, leaving a circumferentially continuous proximalportion free of material. In one embodiment, the entire proximal portionis characterized by a surface having the ability to seal with the innersurface of a selected suspension sleeve such that a moderate vacuum inthe range of from about 2 to 14 inches Hg is maintained for at least 30minutes of ambulatory activity, and more preferably for at least 60minutes of ambulatory activity. In another embodiment, at least acircumferentially continuous subportion of the aforementioned portion ischaracterized by a surface having the foregoing qualities.

It should be noted that the quality of the foregoing seal has adependence on the ability of the inner surface of the suspension sleeveto seal distally with the outer surface of the prosthetic socket at acircumferentially continuous region distal to the socket edge. Thequality of the foregoing seal also depends on the ability of thesuspension sleeve to seal proximally at a circumferentially continuousregion proximal to the material leading edge. By “circumferentiallycontinuous” is meant pertaining to an area which circumscribes. Thus, ingeneral, the suspension sleeve must be long enough to simultaneouslyengage in both seals. Furthermore, the suspension sleeve must have thecombination of physical dimensions such as unstretched and stretchedcircumferences and elastic dimensions such as elasticity, tensilestrength, deformability, and the like to in order to create efficientseals. This is considered to be within the purview of the prior art.Furthermore, the efficiency of the seal depends on the quality of thecontact between the suspension sleeve and the respective surfaces. In apreferred embodiment, the suspension sleeve comprises one material whichforms a seal which can sustain a moderate vacuum in the range of fromgreater than 2 inches Hg to about 14 inches Hg. In other embodiments,the sleeve comprises a material differential from one end to the otherend such that the overall efficiency of sealing the interstitial volumeis improved over the sealing efficiency of the material compositions ofthe respective ends. In another embodiment, the sleeve comprises regionsof two distinct materials which are joined together. In an additionalembodiment, the region of joining comprises horizontal overlap ofregions of the respective. By “horizontal” is meant parallel to thecylindrical axis. In yet another embodiment, an additional component isincluded to enhance the quality of the seal, and, optionally, is used toimprove the efficiency of the seal. Such a component can be an adhesivewhich is mild and temporary such that it improves the vacuum-holdingpower of the seal, yet allows the sleeve to be removed, undamaged by thewearer. In some instances, it may be convenient to use a band or othercircumferential securing mechanism to increase the efficiency of theseal. In other cases bio-sealants or other intermediate layers whichcontact the liner on one side and the suspension sleeve on the other maybe used. The purview of the present invention is considered to encompassmethods or additional measures for improving the vacuum-sustainingability of the seal, even if the seal in the absence of the method ormeasure does not exhibit the ability to maintain a vacuum in the rangeof from 2-14 inches with ambulation, as long as the seal in the presenceof the methods or measures does maintain such efficiency.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross-sectional view of a prior art prosthetic assemblyillustrating the wearer's residual limb (1), a liner having a fabriclayer (2), a prosthetic socket (3) and a suspension sleeve (4) acting asa sealing sleeve between the prosthetic socket and the residual limb.

FIG. 2 is an enlarged cross-sectional view the suspension sleeve (4) asillustrated in FIG. 1.

FIG. 3 is a cross-sectional view of a liner having an elastomeric layer(7) as well as a partial fabric outer layer (6).

FIG. 4 is a cross-sectional view of a prosthetic assembly of the presentinvention showing the wearer's limb (18) within the elastomeric liner(9) having partial overlying material layer (12) mounted withinprosthetic socket (10) and suspension sleeve (11).

FIG. 5 is a cross-sectional view of the prosthetic assembly of thepresent invention similar to FIG. 4 including a locking pin (16)connected to the distal end of the liner (9) and cooperating with alocking assembly mounted in the distal end (15) of the socket (10).

FIG. 6 is an exploded view of the distal end of the prosthetic assemblyof FIG. 5 illustrating the details of the locking pin (16) cooperatingwith the locking assembly mounted in the distal end of the socket andalso the internal passageway through the pin having the one-way valve(19) therein permitting the exit of air from the volume of theinterstitial region (12) to the surrounding atmosphere.

DETAILED DESCRIPTION OF THE INVENTION

FIGS. 1 and 2 illustrate a prior art prosthetic assembly. The linerincludes a fabric layer (2) into which a wearer's prosthetic limb (1) isinserted. The limb/liner combination is inserted into a prostheticsocket (3). The prosthetic socket (3) has a proximal portion adjacent anintermediate portion (5) of fabric layer (2), against which the distalportion of a suspension sleeve (4) can seal, and which extendsproximally, to some extent, up beyond the proximal end (2′) of thefabric layer onto the residual limb (1). The suspension sleeve, in itsproper functioning position, extends proximally from the socket, overthe fabric liner, to the thigh of the patient, against which a seal isformed. A vacuum is established in the volume between the socket, theresidual limb and the suspension sleeve.

FIG. 3 is an illustration of an embodiment of a liner of the presentinvention comprising an elastomeric layer or interface layer (7), and amaterial layer (6) which overlies the distal end of the elastomericlayer. The material layer comprises a leading edge (8). Shown is a fullyrecessed leading edge, in which the material layer is sunken into thesurface of the interface or elastomeric layer.

FIG. 4 is an illustration of another embodiment of the present inventioncomprising a combination prosthetic socket/liner assembly. Theprosthetic socket (10) is preferably a monolithic structure manufacturedby any conventional technique to have an interior surface complementallyconfigured to the residual limb of the amputee. The interface orelastomeric liner (9) has an open proximal end and a closed distal endfor receiving a residual limb (18) fittingly retained therein. The outersurface of the elastomeric liner is distally overlaid with a materiallayer (12), which may be fabric, having a leading edge (13). The liner,when mounted in said socket, having the leading edge (13) act as anintermediate edge disposed adjacent to and within the proximal edge ofsaid socket. The liner, when mounted in this position, having theproximal outer surface region of the liner between the intermediate edgeof the liner and the proximal edge of the socket, sealing against theproximal inner surface of the socket and extending away from saidproximal edge of the socket. The prosthetic assembly also includes asealing open-ended sleeve (11) having a first end and an opposite secondend. The sealing sleeve being mounted in sealing engagement over theproximal outer surface region of said socket and the proximal outersurface region of said liner with the first end overlapping the proximalouter surface region of said socket and said second end overlapping andterminating within the proximal outer surface region of said liner. Ifdesired, an adhesive may be disposed on said proximal outer surfaceregion of said socket and said proximal outer surface region of saidliner, and which is mild and temporary such that it improves thevacuum-holding power of the seal between said sealing sleeve, socket andliner yet allows the sleeve to be removed, undamaged by the wearer.

Thus, with the above sealing arrangement, as the amputee ambulates, airtrapped within the interstitial area occupied by the compressiblematerial is forced to evacuate therefrom through the compressiblematerial and then through the interface between the proximal outersurface region of the liner and the proximal inner surface region of thesocket, through the interface between the proximal outer surface regionof said socket and the sealing sleeve first end overlapping the proximalouter surface region of said socket, and through the interface betweenthe proximal outer surface region of said liner and the sealing sleevesecond end overlapping and terminating within the proximal outer surfaceregion of said liner.

FIG. 5 is an illustration of another embodiment of the present inventionsimilar to FIG. 4 including a locking assembly (15) mounted in thedistal end of the socket (10) comprising a locking pin (16) whichengages a hole or cavity (17) in the prosthetic socket for locking theprosthetic assembly onto the residual limb and which includes anotherair exit flow path for evacuating air within the interstitial regionoccupied by the compressible material.

FIG. 6 is an exploded view of the locking assembly in the distal end ofthe socket illustrated in FIG. 5. A pin receiving housing (25) ismounted within the distal end of socket (10) and includes a hole orcavity (17) therethrough for receiving locking pin (16). The locking pin(16) has an upper radially extending flange (24) with one or morelaterally extending passageways (22). The locking pin further includesan axially extending passageway (20) fluidically communicating with theone or more lateral passageways (22) which, it turn, are in fluidiccommunication with the interstitial volume occupied by material orfabric layer (12) bound by liner (9) and socket (10). The passageway(20) includes a one-way valve (19) therein which may be any typical typeof one-way valve such as a duck-bill valve or spring biased ball checkvalve. An O-ring (23) is disposed in an annular recess (26) to provide asealing engagement between the pin flange (24) and the pin receivinghousing (25). Although FIG. 6 shows a single O-ring (23), it iscontemplated that any type of sealing means could be employed as alongas the air passage is restricted to flow from the interstitial volumethrough the one-way valve (19) and out through the passageway (20). Thelocking assembly (15) further includes a locking ratchet wheel (21) forengaging annular recesses on the locking the pin (16) for locking thepin within hole (17). It is noted that the locking assembly is notlimited to that shown in the drawings wherein pin (16) could have adifferent exterior configuration that would cooperate with any othertype of locking mechanism as, for example, the locking assemblydisclosed in U.S. Pat. No. 7,427,298 which is incorporated herein byreference in its entirety.

Furthermore, although not shown in FIG. 6, the distal end of the socket(10) may be configured to be connected to a pylon of a prosthetic leg(not shown) via any commercially available mechanism such as the onedisclosed in U.S. Pat. No. 3,659,294 which is incorporated herein byreference.

The foregoing relates to the preferred exemplary embodiments of theinvention, it being understood that other variants and embodimentsthereof are possible within the spirit and scope of the invention, thelatter being defined by the appended claims.

1. A prosthetic assembly comprising: a) a monolithic prosthetic sockethaving an inner surface and an outer surface, a closed distal end and anopen proximal end; said inner surface configured to substantially becomplimentary to the shape of a residual limb of an amputee; said sockethaving a proximal end edge and a proximal outer surface regionsurrounding said open proximal end; b) a prosthetic liner having aninner surface and an outer surface, a closed distal end and an openproximal end; said inner surface adapted to conform to the shape of theresidual limb of the amputee such that said limb is fittingly retainedtherein when donned; said liner having a proximal outer surface regionsurrounding said proximal open end extending from a proximal end edge ofsaid liner to an intermediate edge thereon; said liner having a distalouter surface region extending from said intermediate edge to saiddistal end and being covered with a porous or continuously cavitatedcompressible material having an outer surface; said proximal outersurface region of said liner and said outer surface of said compressiblematerial defining a substantially collinear outer surface with thecompressible material layer being recessed into said liner to a distanceof about the thickness of the compressible material; c) said liner beingmounted within said socket such that said outer surface of saidcompressible material is fittingly received in said socket and in directcontact with the inner surface of said monolithic socket from saidintermediate edge to said distal end of said liner to thereby define andsustain an interstitial area between the inner surface of said socketand the outer surface of said liner through said compressible material;d) said liner, when mounted in said socket, having said intermediateedge disposed proximate said proximal edge of said socket and withinsaid socket such that said proximal outer surface region of said lineris in direct contact with the inner surface of said monolithic socketfrom said intermediate edge of said liner to said proximal end edge ofsaid socket and extends away from said proximal end edge of said socket;e) a sealing open-ended sleeve having a first end and an opposite secondend; said sealing sleeve mounted in sealing engagement over saidproximal outer surface region of said socket and said proximal outersurface region of said liner with said first end overlapping saidproximal outer surface region of said socket and said second endoverlapping and terminating within said proximal outer surface region ofsaid liner; whereby as said amputee ambulates, air trapped within saidinterstitial area is forced to evacuate therefrom through saidcompressible material, through the interface between said proximal outersurface region of said liner and the inner surface of said monolithicsocket from said intermediate edge of said liner to said proximal endedge of said socket and through the interface between said sealingsleeve, said proximal outer surface region of said socket and saidproximal outer surface region of said liner; f) said liner, saidcompressible material and said sealing sleeve comprising materialsselected such that a vacuum from above about 0 inches Hg to about 15inches Hg is capable of being maintained in said interstitial area uponambulatory motion; and g) said socket includes a distally located holeor cavity extending therethrough and said liner comprises a locking pinin the distal end which engages said hole or cavity in the distal end ofsaid socket for locking the prosthesis onto the residual limb of theamputee, said pin further includes an axially extending passageway witha one-way valve mounted therein for permitting exit of air in the volumeof said interstitial area during ambulation of the amputee; h) whereby acircumferentially continuous sealable interface between said liner andsaid socket together with a circumferentially continuous sealableinterface between said sleeve and said liner provides sufficient sealingstructure free of any concentrated annular pressure points to accomplishsaid vacuum within said prosthetic assembly.
 2. A prosthetic assembly asclaimed in claim 1, wherein said liner is made from an elastomer andsaid compressible material is a fabric or foam.
 3. A prosthetic assemblyas claimed in claim 2, wherein said elastomer comprises one or more ofthe polymer materials from the list consisting of the following types:polyurethane, polybutylene, polypropylene, and styrene block copolymers.4. A prosthetic assembly as claimed in claim 2, wherein said fabric orfoam is bonded to said liner.
 5. A prosthetic assembly as claimed inclaim 1, wherein said liner is made from an elastomer and saidcompressible material is formed by treating the outer surface of theelastomer to cause the outer surface to form a foam.
 6. A prostheticassembly as claimed in claim 1, wherein said liner, said compressiblematerial and said sealing sleeve comprising materials selected such thatsaid vacuum is from about 2 inches Hg to about 14 inches Hg and iscapable of being maintained in said interstitial area upon ambulatorymotion.
 7. A prosthetic assembly as claimed in claim 1, wherein saidliner, said compressible material and said sealing sleeve comprisingmaterials selected such that said vacuum is from about 5 inches Hg toabout 12 inches Hg and is capable of being maintained in saidinterstitial area upon ambulatory motion.
 8. A prosthetic assembly asclaimed in claims 1, further including an adhesive, disposed on saidproximal outer surface region of said socket and said proximal outersurface region of said liner, and which is mild and temporary such thatit improves the vacuum-holding power of the seal between said sealingsleeve, socket and liner yet allows the sleeve to be removed, undamagedby the wearer.
 9. A prosthetic assembly as claimed in claim 1, wherein alength of the elastomeric liner from said open proximal end to closeddistal end is in the range of from 9 to 24 inches; and wherein saidcompressible material on the outer surface of said liner extends fromthe closed distal end for a distance in the range of from about 4 to 21inches toward the open proximal end thereby not reaching said openproximal end.
 10. A prosthetic assembly as claimed in claim 1, wherein alength of the elastomeric liner from said open proximal end to closeddistal end is in the range of from 8 to 20 inches; and wherein saidcompressible material on the outer surface of said liner extends fromthe closed distal end for a distance in the range of from about 4 to 16inches toward the open proximal end thereby not reaching said openproximal end.
 11. A prosthetic assembly as claimed in claim 1, whereinsaid locking pin further comprises a first end connected to said distalend of said liner and defining a flange with at least one laterallyextending passageway in fluidic communication with said axiallyextending passageway.
 12. A prosthetic assembly as claimed in claim 11,wherein said flange is in sealing engagement with a pin receivinghousing whereby air flow from said interstitial region is restricted toflow from said interstitial region through said at least one lateralpassageway, through said one-way valve and out through said axiallyextending passageway.
 13. A prosthetic assembly as claimed in claim 12,wherein said sealing engagement comprises an O-ring.
 14. A prostheticassembly as claimed in claim 1, wherein said socket distal end has a pinreceiving housing mounted therein and defining said hole or cavity forreceiving said locking pin.
 15. A prosthetic assembly as claimed inclaim 14, wherein said pin and said pin receiving housing furthercomprise a locking mechanism for locking said pin in said hole orcavity.
 16. A prosthetic assembly as claimed in claim 15, wherein saidlocking mechanism comprises a ratchet wheel.